The Marathon Trilogy is a science fiction first-person shooter video game series from Bungie, primarily released for the Mac OS. The name of the series is derived from the giant interstellar colony ship that provides the main setting for the first game; the ship is constructed out of the Martian moon Deimos. The three games in the series — Marathon (1994), Marathon 2: Durandal (1995), and Marathon Infinity (1996) — are widely regarded as spiritual predecessors of Bungie's Halo series.